This invention relates to signal lights of the type used on emergency vehicles, and in particular to such signal lights that are oscillable in two directions.
Various lights that oscillate in two directions, for example in the horizontal and vertical directions, are known. The majority of these lights trace a simple, repetitive pattern, for example an "X" or a FIG. 8. Examples of such devices may be found in U.S. Pat. Nos. 2,409,046, 2,510,892, 4,511,880, and 4,530,037. These devices are usually unsatisfactory as signals because the beams of their lights do not sweep all areas within the perimeter of the pattern, resulting in substantial gaps or blind spots in the pattern. Another problem with these prior signal lights is that their mechanisms are usually extremely complicated. Another problem with these prior lights is that it is difficult to change the pattern that the light traces. Co-assigned U.S. Pat. No. 4,388,609, solves many of these problems, but does not provide all of the advantages of the present invention.